Duration: 12 months
Earth Observation using GNSS opportunity signals has confirmed its appeal through the recent spread of missions, like the NASA CYGNSS and the forthcoming ESA Scout HydroGNSS. The growing investments into Low Earth Orbit SatComs are going to offer new and unique benefits, as multiple companies are deploying mega satellite constellations to provide global broadband internet. The proposed study aims at demonstrating the feasibility of microwave reflectometry using signals from the OneWeb constellation of satellites. The Ku-band wavelength characterising these signals is widely used and very suitable for sensing crucial geophysical parameters of land (e.g., soil moisture), ocean (e.g., wind speed), cryosphere (snow and sea ice properties) and atmosphere (e.g., rain rate). The limitations coming from the poor knowledge of the transmitted signals can be in principle overcome when the interferometric configuration is adopted, with Nadir/Zenith pointed antennas measuring the reflected/direct signals. The work will focus on the development of a simulator which reproduces the signal transmission and scattering from synthetic surfaces with specified characteristics and the signal reception using realistic assumptions on antenna and hardware, implementing a suitable processing approach for this specific application. The simulator will be strongly based on a pre-existing GNSS-Reflectometry simulator developed by University of Sannio and will be re-adapted to simulate the reflections and reception of OneWeb signals. The possibility of varying input parameters related to the properties of the scattering surface and of adjusting the processing parameters in an optimal way will allow a sensitivity analysis of the response of the reflections to the geophysical properties of interest from the Earth surface. If successful, the project could represent the first step towards a novel NewSpace application and could potentially demonstrate improved sensing of Earth surface parameters.
